Interface superconductivity in FeSe thin films on SrTiO${}_3$grown by the PLD technique

Abstract

In this study, we fabricate 5-30-nm-thick films of FeSe/STO using pulsed laser deposition (PLD). The grown films exhibit superconductivity with an onset $T_{\mathrm{c}}$ that is much higher than that of bulk FeSe under ambient pressure. The observed $T_{\mathrm{c}}$ values are exceptionally high in terms of the strain vs. $T_{\mathrm{c}}$ relationship of the same material established so far. Furthermore, $T_{\mathrm{c}}$ increases as the film thickness decreases, except for films thinner than 10 nm. This thickness dependence of $T_{\mathrm{c}}$ is in good agreement with the results reported for films grown by molecular beam epitaxy (MBE) that exhibit interface superconductivity. These results indicate the realization of interface superconductivity in PLD-grown FeSe/STO. Furthermore, our PLD technique requires no post-annealing to realize interface superconductivity, which is different from MBE techniques. Because the PLD technique has the advantage that various interfaces can be fabricated easily by simply altering the target materials, our results open novel routes to study interface superconductivity toward higher $T_{\mathrm{c}}$ by systematic control of the interface.

10 pages, 4 figures

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Cited by in corpus (4)

• Anisotropy of upper critical fields and interface superconductivity in FeSe/SrTiO3 grown by PLD
• Study on fluctuations of interface-enhanced superconductivity in ultrathin FeSe/SrTiO3 by the Nernst effect
• Studies of superconductivity of Fe chalcogenides in films grown by PLD technique
• Fabrication of oxide/FeSe multilayer films using the PLD technique